# join()   字符串作为连接符，将给定的字符序列连接成新的字符串
print('-'.join('hello'))  
# max()  返回值最大的字符
print(max('hellojavaw')) 
# min()  返回最小的字符
print(min('hellojava')) 

# format()    
print("My name is {name}, I am {age}".format(name='zhangsan',age=20)) 